The Galapagos Islands are known throughout the world as a home to unique flora and fauna, including exotic birds, marine iguana and giant tortoises.

The wildlife was the inspiration for British naturalist Charles Darwin's theory of natural selection.

The islands were the first place on the planet officially designated as a World Heritage site, but last year the UN Environment, Scientific and Cultural Organisation (Unesco), which administers the list of sites, declared the Galapagos "in danger".

Experts said the 19 islands and surrounding ocean were under threat from "invasive species", increased tourism and growing immigration.

In a statement, the organisation said international interest in the islands - which are Ecuador's most popular tourist attraction - was contributing to their gradual decline.